Add DataRowReader and change Connection.SelectFunc to use it

Preparatory step for structure binding. refs #11

data_row_reader_test.go

@@ -0,0 +1,117 @@
+package pgx
+
+import (
+	"testing"
+)
+
+func TestDataRowReaderReadString(t *testing.T) {
+	conn := getSharedConnection()
+
+	var s string
+	onDataRow := func(r *DataRowReader) error {
+		s = r.ReadString()
+		return nil
+	}
+
+	err := conn.SelectFunc("select 'Jack'", onDataRow)
+	if err != nil {
+		t.Fatal("Select failed: " + err.Error())
+	}
+	if s != "Jack" {
+		t.Error("Wrong value returned")
+	}
+}
+
+
+func TestDataRowReaderReadInt64(t *testing.T) {
+	conn := getSharedConnection()
+
+	var n int64
+	onDataRow := func(r *DataRowReader) error {
+		n = r.ReadInt64()
+		return nil
+	}
+
+	err := conn.SelectFunc("select 1", onDataRow)
+	if err != nil {
+		t.Fatal("Select failed: " + err.Error())
+	}
+	if n != 1 {
+		t.Error("Wrong value returned")
+	}
+}
+
+func TestDataRowReaderReadInt32(t *testing.T) {
+	conn := getSharedConnection()
+
+	var n int32
+	onDataRow := func(r *DataRowReader) error {
+		n = r.ReadInt32()
+		return nil
+	}
+
+	err := conn.SelectFunc("select 1", onDataRow)
+	if err != nil {
+		t.Fatal("Select failed: " + err.Error())
+	}
+	if n != 1 {
+		t.Error("Wrong value returned")
+	}
+}
+
+func TestDataRowReaderReadInt16(t *testing.T) {
+	conn := getSharedConnection()
+
+	var n int16
+	onDataRow := func(r *DataRowReader) error {
+		n = r.ReadInt16()
+		return nil
+	}
+
+	err := conn.SelectFunc("select 1", onDataRow)
+	if err != nil {
+		t.Fatal("Select failed: " + err.Error())
+	}
+	if n != 1 {
+		t.Error("Wrong value returned")
+	}
+}
+
+
+
+func TestDataRowReaderReadFloat64(t *testing.T) {
+	conn := getSharedConnection()
+
+	var n float64
+	onDataRow := func(r *DataRowReader) error {
+		n = r.ReadFloat64()
+		return nil
+	}
+
+	err := conn.SelectFunc("select 1.5", onDataRow)
+	if err != nil {
+		t.Fatal("Select failed: " + err.Error())
+	}
+	if n != 1.5 {
+		t.Error("Wrong value returned")
+	}
+}
+
+func TestDataRowReaderReadFloat32(t *testing.T) {
+	conn := getSharedConnection()
+
+	var n float32
+	onDataRow := func(r *DataRowReader) error {
+		n = r.ReadFloat32()
+		return nil
+	}
+
+	err := conn.SelectFunc("select 1.5", onDataRow)
+	if err != nil {
+		t.Fatal("Select failed: " + err.Error())
+	}
+	if n != 1.5 {
+		t.Error("Wrong value returned")
+	}
+}
+